SHELL STRUCTURE  Shell is a type of building enclosures.  Shells belong to the family of arches . They can be defined as curved or angled structures capable of transmitting loads in more than two directions to supports.  A shell with one curved surface is known as a vault (single curvature ).  A shell with doubly curved surface is known as a dome (double curvature). CONTINUITY & CURVATURE  ls are structurally continuous in the sense that they can transmit forces in a number of different directions in the surface of the shell, as required.  Shell structures have quite a different mode of action from skeletal structures, of which simple examples are trusses, frameworks, and trees because other structures are only capable of transmitting forces along their discrete structural members. CLOSED & OPEN SHELL  Anyone who has built children’s toys from thick paper or thin cardboard will be familiar with the fact that a closed box is rigid, whereas an open box is easily deformable. The same sort of thing applies in shell structure.  Close surfaces are rigid. In practice it is not usually possible to make completely closed structural boxes. CLOSED & OPEN SHELL  For shell with openings, reinforce the edge of the hole in such a way as to compensate, to a certain extent, for the presence of the hole. The amount of reinforcement required depends on the size of the hole, and to what extent the presence of the whole makes the structure an open one.  Large openings are essential in some forms of construction, like in shell roof. CLASSIFICATION OF SHELLS There are many different ways to classify shell structures but two ways are common: 1. The material which the shell is made of: like reinforced concrete, plywood or steel, because each one has different properties that can determine the shape of the building and therefore, these characteristics have to be considered in the design. 2. The shell thickness: shells can be thick or thin. Felix Candela A Spanish and Mexican architec t who acknowledged as a master builder and structural artist who designed and built great thin shell concrete roof structures of the hyperbolic paraboloid geometric form in Mexico. THIN CONCRETE SHELLS  The thin concrete shell structures are a lightweight construction composed of a relatively thin shell made of reinforced concrete, usually without the use of internal supports giving an open unobstructed interior.  The shells are most commonly domes and flat plates, but may also take the form of ellipsoids or cylindrical sections, or some combination thereof.  Most concrete shell structures are commercial and sports buildings or storage facilities. THIN CONCRETE SHELLS  The thin concrete shell structures are a lightweight construction composed of a relatively thin shell made of reinforced concrete, usually without the use of internal supports giving an open unobstructed interior.  The shells are most commonly domes and flat plates, but may also take the form of e

1. SHELL STRUCTURE

2.  Shell is a type of building enclosures.
 Shells belong to the family of arches . They can be
defined as curved or angled structures capable of
transmitting loads in more than two directions to
supports.
 A shell with one curved surface is known as a vault
(single curvature ).
 A shell with doubly curved surface is known as a dome
(double curvature).
SHELL STRUCTURE
SHELL STRUCTURE

3.  ls are structurally continuous in the sense that they can
transmit forces in a number of different directions in
the surface of the shell, as required.
 Shell structures have quite a different mode of action
from skeletal structures,
of which simple examples are
trusses, frameworks, and trees
because other structures are
only capable of transmitting
forces along their discrete
structural members.
SHELL STRUCTURE
CONTINUITY & CURVATURE

4.  Anyone who has built children’s toys from thick paper or
thin cardboard will be familiar with the fact that a closed
box is rigid, whereas an open box is easily deformable.
The same sort of thing applies in shell structure.
 Close surfaces are rigid.
 In practice it is not usually
possible to make completely
closed structural boxes.
SHELL STRUCTURE
CLOSED & OPEN SHELL

5.  For shell with openings, reinforce the edge of the hole
in such a way as to compensate, to a certain extent, for
the presence of the hole. The amount of reinforcement
required depends on the size of the hole, and to what
extent the presence of the
whole makes the structure an
open one.
 Large openings are
essential in some forms of
construction, like in shell roof.
SHELL STRUCTURE
CLOSED & OPEN SHELL

6.  There are many different ways to classify shell structures
but two ways are common:
1. The material which the shell is made of: like
reinforced concrete, plywood or steel, because each
one has different properties that can determine the
shape of the building and therefore, these
characteristics have to be considered in the design.
2. The shell thickness: shells can be thick or thin.
SHELL STRUCTURE
CLASSIFICATION OF SHELLS

7. Felix Candela
 A Spanish and Mexican architec
t who acknowledged as a master
builder and structural artist who
designed and built great thin
shell concrete roof structures of
the hyperbolic paraboloid
geometric form in Mexico.
SHELL STRUCTURE

8.  The thin concrete shell structures are a lightweight
construction composed of a relatively thin shell made of
reinforced concrete, usually without the use of internal
supports giving an open unobstructed interior.
 The shells are most commonly domes and flat plates,
but may also take the form of ellipsoids or cylindrical
sections, or some combination thereof.
 Most concrete shell structures are commercial
and sports buildings or storage facilities.
SHELL STRUCTURE
THIN CONCRETE SHELLS

9.  The thin concrete shell structures are a lightweight
construction composed of a relatively thin shell made of
reinforced concrete, usually without the use of internal
supports giving an open unobstructed interior.
 The shells are most commonly domes and flat plates,
but may also take the form of ellipsoids or cylindrical
sections, or some combination thereof.
 Most concrete shell structures are commercial
and sports buildings or storage facilities.
SHELL STRUCTURE
THIN CONCRETE SHELLS
The Oceanographic
Felix Candela

10.  The thin concrete shell structures are a lightweight
construction composed of a relatively thin shell made of
reinforced concrete, usually without the use of internal
supports giving an open unobstructed interior.
 The shells are most commonly domes and flat plates,
but may also take the form of ellipsoids or cylindrical
sections, or some combination thereof.
 Most concrete shell structures are commercial
and sports buildings or storage facilities.
SHELL STRUCTURE
THIN CONCRETE SHELLS
AUDITORIO DE TENERIFE
Santiago Calatrava

11.  The thin concrete shell structures are a lightweight
construction composed of a relatively thin shell made of
reinforced concrete, usually without the use of internal
supports giving an open unobstructed interior.
 The shells are most commonly domes and flat plates,
but may also take the form of ellipsoids or cylindrical
sections, or some combination thereof.
 Most concrete shell structures are commercial
and sports buildings or storage facilities.
SHELL STRUCTURE
THIN CONCRETE SHELLS
CHURCH OF THE RISEN LORD
Cesar Concio

12.  The thin concrete shell structures are a lightweight
construction composed of a relatively thin shell made of
reinforced concrete, usually without the use of internal
supports giving an open unobstructed interior.
 The shells are most commonly domes and flat plates,
but may also take the form of ellipsoids or cylindrical
sections, or some combination thereof.
 Most concrete shell structures are commercial
and sports buildings or storage facilities.
SHELL STRUCTURE
THIN CONCRETE SHELLS
PARISH OF THE HOLY SACRIFICE
Leandro Locsin

13.  Shape - The first factor is the shape which was
developed along the history of these constructions. Some
shapes were resistant and can be erected easily.
However, the designer’s incessant desire for more
ambitious structures did not stop and new shapes were
designed.
 Thickness, which is usually less than 10 centimeters.
For example, the thickness of the Hayden planetarium
was 7.6 centimeters
SHELL STRUCTURE
FACTORS IN THE DEVT OF THIN SHELLS

14. 1. BARREL SHELLS
2. FOLDED PLATE
3. HYPERBOLIC PARABOLOID
4. VARIOUS DOUBLE CURVATURE
5. DOME
6. TRANSLATION SHELLS
SHELL STRUCTURE
TYPES OF THIN CONCRETE SHELLS

15.  The cylindrical thin shells,
also called barrels, should not
be confused with the vaults
even with the huge similarity
in the shape of both
structures, because each of
these structures has a
different structural behavior as
well as different requirements
in the minimum thickness and
the shape.
SHELL STRUCTURE
1. BARREL SHELLS

16.  On one hand, the structural behavior of the barrels
shell is that it carries load longitudinally as a beam
and transversally as an arch. and therefore, the
materials have to resist both compression and
tension stresses.
 shape has fewer requirements than
the vaults and therefore, new curves
like the ellipse or the parabola can
used improving the aesthetic quality
of the structure.
SHELL STRUCTURE
1. BARREL SHELLS

17.  On the other hand, the
structural behavior of the vault
is based on connected
parallel arches, which
transmit the same effort to the
supports . Therefore, the
materials used in these
structures have to be able to
resists compressions (e.g.
stone) and the thickness is
usually higher.
SHELL STRUCTURE
WHAT IS VAULT?

18.  A thin-walled building structure of the shell type.
Advantages :
(a) Movable form work can be employed.
(b) Requires simplier form work
(c) Design involves simpler calculations.
Disadvantages of Folded Plate Roofs over Shell Roofs are:
(a) Folded plate consumes more material than shells.
(b) Form work may be removed after 7 days whereas in
case of shells it can be little earlier.
SHELL STRUCTURE
2. FOLDED PLATE

19. SHELL STRUCTURE
2. FOLDED PLATE

20. SHELL STRUCTURE
2. FOLDED PLATE

21. SHELL STRUCTURE
2. FOLDED PLATE

22. SHELL STRUCTURE
2. FOLDED PLATE

23. SHELL STRUCTURE
2. FOLDED PLATE

24.  is a doubly-curved
surface that resembles
the shape of a saddle,
that is, it has a convex
form along one axis,
and a concave form on
along the other.
SHELL STRUCTURE
2. HYPERBOLIC PARABOLOID

25.  A Hypar is a surface curved in two
directions that can be designed as
a shell or warped lattice.
 A hypar is triangular, rectangular or
rhomboidal in plan, with corners
raised to the elevation desired for
use and/or appearance. The edges
of Hypars are typically restrained by
stiff hollow beams that collect &
transfer roof loads to the
foundations.
SHELL STRUCTURE
2. HYPERBOLIC PARABOLOID

26.  The thin concrete shell structures are a lightweight
construction composed of a relatively thin shell made of
reinforced concrete, usually without the use of internal
supports giving an open unobstructed interior.
 The shells are most commonly domes and flat plates,
but may also take the form of ellipsoids or cylindrical
sections, or some combination thereof.
 Most concrete shell structures are commercial
and sports buildings or storage facilities.
SHELL STRUCTURE
THIN CONCRETE SHELLS
SYDNEY OPERA HOUSE
Jorn Utzon

27.  The thin concrete shell structures are a lightweight
construction composed of a relatively thin shell made of
reinforced concrete, usually without the use of internal
supports giving an open unobstructed interior.
 The shells are most commonly domes and flat plates,
but may also take the form of ellipsoids or cylindrical
sections, or some combination thereof.
 Most concrete shell structures are commercial
and sports buildings or storage facilities.
SHELL STRUCTURE
TWA FLIGHT CENTER
Eero Saarinen

28. SHELL STRUCTURE
2. HYPERBOLIC PARABOLOID

29. SHELL STRUCTURE
2. HYPERBOLIC PARABOLOID

30. SHELL STRUCTURE
4. VARIOUS DOUBLE CURVATURE

31. SHELL STRUCTURE
4. VARIOUS DOUBLE CURVATURE

32. ZAHA HADID
 She was the first woman
to receive the Pritzker
Architecture Prize, in 2004.
 She was described by The
Guardian of London as the
"Queen of the curve", who
"liberated architectural
geometry, giving it a whole
new expressive identity“.
SHELL STRUCTURE

33. SHELL STRUCTURE
4. VARIOUS DOUBLE CURVATURE
HEYDAR ALIYEV CENTER
Zaha Hadid

34. SHELL STRUCTURE
4. VARIOUS DOUBLE CURVATURE
HEYDAR ALIYEV CENTER
Zaha Hadid

35. SHELL STRUCTURE
4. VARIOUS DOUBLE CURVATURE
HEYDAR ALIYEV CENTER
Zaha Hadid
GALAXY SOHO
Zaha Hadid

36.  A rounded roof, with a circular base,
shaped like an arch in all
directions.
 Dome has double curvature and the
resulting structure is much stiffer and
stronger than a single curved
surface, such as a barrel shell.
 First used in much of the Middle
East and North Africa whence it
spread to other parts of the Islamic
world.
SHELL STRUCTURE
5. DOME

37. SHELL STRUCTURE
4. DOME

38.  A translation shell is a
dome set on four arches.
 The shape is different from
a spherical dome and is
generated by a vertical
circle moving on another
circle.
 All vertical slices have the
same radius. It is easier to
form than a spherical dome.
SHELL STRUCTURE
6. TRANLATIONAL SHELLS